1. Field of the Invention
This invention relates generally to mounting systems. In particular, it relates to mounting systems for attaching accessory items to a truck bed.
2. Description of the Prior Art
Devices for mounting and retaining truck bed accessories are well known in the art. The type of device utilized to secure an accessory item to a truck varies depending on the size and construction of the item to be mounted. Although clearly not exhaustive, examples of mountable truck bed accessories include tonneau covers, truck caps, truck bed campers, vinyl covers, and various decorative rails and lights.
One type of mounting device is simply a screw or threaded bolt and nut combination extending through the item to be mounted and into or through the truck bed sidewall. Use of such a mounting system requires that the truck bed have either preformed mounting holes or that holes be punched or drilled in the truck bed prior to mounting of the accessory. A problem with having preformed mounting holes is that there are a wide variety of truck bed accessory items, thereby making it impractical to preform mounting holes in the truck bed in an attempt to make every accessory item mountable without additional modification. Therefore, preformed mounting holes are rare for most truck bed accessories.
An alternative approach is to drill or punch a series of mounting holes in a portion of the truck bed sidewall suitable for mounting an accessory. The drilling or punching operation damages the truck bed finish and modifies the original condition of the truck. The damage to the truck bed finish creates an area where the truck bed may corrode over time. Moreover, if the accessory item is later removed, body work and painting will be required to return the truck to its original condition.
In an effort to overcome the drawbacks of fasteners which penetrate the sidewall of the truck bed, numerous clamping systems have been utilized. Many of these systems rely on a mounting rail or some other rigid member to rest upon the upper, horizontal surface of the sidewall. Typically, a nonabrasive material, commonly cab tape, is placed between the mounting rail and the truck bed to prevent damage to the truck bed finish. The accessory item is then securely attached to the mounting rail.
In one such device, a clamping member consisting of an upper and a lower clamping bracket interconnected by a threaded fastener can be used to clamp the mounting rail to the truck bed sidewall. The clamp in many respects resembles a vise with both ends of the clamp being driven towards one another by the threaded shaft. The upper clamping bracket extends over the top of the mounting rail and the lower clamping bracket extends under the horizontal portion of the sidewall. The threaded shaft connects the two clamp brackets and is operated to urge the clamping members together. The upper clamping bracket exerts a downward force on the rail, while the lower clamping bracket exerts a corresponding upward force on the underside of the truck bed sidewall. One drawback of this system is that the upper clamping member must extend above the uppermost surface of the mounting rail, thereby interfering with placement of items on the mounting rail and movement of cargo into and out of the truck bed. Another drawback is that the system clamps only a substantially horizontal portion of the sidewall; thus the mounting rail is not clamped to a vertical portion of the sidewall and may permit some degree of movement in the horizontal plane.
Several alternative rail and clamp combinations have been disclosed in an attempt to overcome the problems of the early vise-type clamp design. In some of these designs the mounting rail includes a vertical portion extending into the interior of the truck bed. The vertical portion includes a slot to receive a portion of the clamping system, thereby permitting the upper clamp to be located below the horizontal surface of the rail. Thus, items can be mounted flush with the upper surface of the rail. In many of these designs the rail is provided with a clamp mounting groove preformed into the rail for receiving an upper portion of either a clamp bracket or a threaded tightening member. Several designs have disclosed a "T" slot formed the entire length of the rail of the vertical surface facing towards the interior of the truck bed. A bolt or clamp member with a corresponding "T" end is inserted into the "T" slot and slid along the "T" slot until the desired clamping location is reached. In one device a clamping bracket is substantially a "C"-shaped clamping bracket. One end of the clamping bracket has a projection corresponding to the "T" slot while the other end has a threaded opening for receiving a threaded member. The threaded member is threaded through the opening and tightened until it exerts an upward force on the underside of the horizontal sidewall disposed beneath the rail. In this manner, the mounting rail is clamped to the truck bed.
In another similar arrangement, the head of a bolt is held in a slot defined on the vertical portion of the rail and extends in a vertical direction toward the floor of the truck bed. A clamp is positioned over the threaded end of the bolt and a nut is tightened until the clamp exerts an upward force on the underside of the horizontal sidewall disposed beneath the rail. Still a further design has a first clamp bracket which slides along the "T" slot and extends at an angle into the interior of the truck bed. The first clamp bracket has an opening for receiving a threaded member. A second clamp bracket slidingly engages the first clamp bracket and extends under the vertical portion of the truck bed sidewall to engage the horizontal portion of the sidewall disposed beneath the rail. Upon tightening the threaded member the second clamp portion clamps the rail to the horizontal sidewall.
It should be appreciated that since the "T" slot is formed on the vertical surface of the mounting rail extending into the interior of the truck bed, insertion of the clamp or bolt member into the slot results in the clamping member extending even further into the truck bed. Thus, many of these designs decrease the usable cargo space in the truck bed and may interfere with loading and unloading. Moreover, in many applications, forming a "T" slot along the entire length of the mounting rail increases the amount of material required to manufacture the rail and thereby increases the cost.
While the latter systems have created a clamping system which uses the rail itself as the upper clamping bracket, thereby permitting flush attachment of accessory items to the upper surface of the rail, these systems still unnecessarily extend into the cargo area of the truck bed. Moreover, although some of the mounting rails have a vertical portion to engage a vertical sidewall of the truck, the systems do not include a clamping member to securely clamp the vertical portion of the mounting rail to the truck bed.
Therefore, there remains a need for a rail mounting system that is capable of clamping both the vertical and horizontal segments of the truck sidewall. Further, the mounting system should have a low profile both with respect to the horizontal and the vertical surfaces of the rail. Finally, the system should be designed to permit easy and secure installation to a wide variety of truck bed styles with a minimum of components.